Shot-firing device



J. A. MAcD0NALD..

SH OT FIRING DEVICE.

APPLICATION FILED SEPT 91 1920.

1,377,086. v Patented May 3,1921.

Inn W/ii/ f DONALD, subject of the fKing of Great W e re s SHOT-FIRING DEVICE.

is'rae'ee.

Specification of Letters Patent.

application filed September 9, 1920., Serial No. 409,244.

To all whom it may concern." I

' Be it known that I, JOHN ANGUs MAC- Britain, residing at Blairmore, Province of Alberta, Canada, have invented certain new and useful Improvements in Shot-Firing Devices; and I do hereby declare that the following is a full, clear, and exact descripcontact, and means for connecting the curtion and in which tion of" the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The present invention relates to improvements in shot firing devices. v

The primary object of the invention is the provision of a shot firing device including a battery box, means for containing batteries, and means for closing the circuit and electrically firing a shot. r V

' Another object of the invention is the provision in a device such as above referred to of a safety means for rendering prematurefiring of the charge impossible.

A further object of the invention is the provision of a. shot firing device including a battery box having batteries therein, and spring contact Inembers'for closing the circuit of the batteries normally held out of rent conveying wires to one set of spring circuit closing members.

' A still further object of the invention is the provision of a shot firing apparatus such as above referred to which will be comparatively simple and inexpensive to manufacture, eliminating a number of the parts in usual devices of this construction, and which will be reliable and efficient in use and readily operated.

With the above and other objects in View, the present invention resides in the novel features of construction, formations, combinations and arrangements of parts to be hereinafter more fully described, claimed, and illustrated in the accompanying drawings forming a part of the present applica- Figure 1 is a perspective view of a portion of a shot firing device constructed in accordance with the present lnventlon;

Fig. 2 is a longitudinal sectional view.

thereof;

Fig. 3 is a detail sectional'view illustrating one of the operating plungers in circuit closing position; and,

Fig. 4 is a fragmental portion of the cover showin the safety slide.

Referring now to the accompanying draw mg by corresponding characters of reference throughout the several views, the numeral; 1 denotes in general a battery box, the up; per portion only of which is shown, as the box itself forms no part of the invention.

The box 1 is provided with a' suitable closure 2 hinged at one end at 3 to the upper edge of the box 1. One or more batteries shown at 4i may be placed within the box,

the same having the usual terminals or con fr orrics."

Patented May :3, 192 1;

tact posts 5 and 6 through'which current is,

conveyed by means of the fieXiblejcO l luctors 7 to the charge which is to be fired.

The cover 2 directly above the contact posts 5 and 6 is provided with openings 8 which may be closed by slides 9 mountedin guides 10 secured to the upper side of the cover 2.

Plungers 11 are mounted in alinement with the openings 8 to pass therethrough and 1 are supported atthe upper ends of the springs 12 which are secured-to the coverfz 1n concentric relation to theopenings '8 .by

any suitable means.

7 The springs 12 which support plungers 11 also carry handles or kno'bs 13 preferably of cork; the bodies 14 and the metal" facings 15 on the same may be constructed of any other desired non conducting ma-.

terial.

The conductors? previously referred'to' have secured to their innerfends collars 16. which are slipped over' the plungers ll, and when the wires or conductors 7 are inserted between the upper convolutions of the spring, these collars 16 form a contact means for securing-the said conductors to the plungers.

Contact plates 17 are supported by springs 18 beneath the openings 8. These plates 17 are yieldingly forced against the insulating I washers 19 secured to the inner sides of the cover 2 andv which hold the contact plates 17 out of engagement therewith. The springs 18 are secured to the upper portion of the batteries 4 in any suitable mannerand surround the contact posts'5 and 6, as clearly shown in Fig. 1. l

When it is desired to fire a charge, the

slides 9 are drawn to the position shown in Fig. 4 which leaves the plungers 11 free topass through the openings 8 into contact with the members 17. Further pressure upon the knobs 13 will force these contact members downwardly into engagement with the posts'5 and 6, thereby closing the circuit and firing the charge. Such position is clearly shown in, Fig. 3 of the drawing.

When the slides 9 are moved inwardly to close the openings 8, it will be obvious that the plungers 11 will be prevented from entering the openings 8 and engaging the contact members 17, thus preventing any premature firing of the charge. It will be understood in this connection that the device described as a shot firing apparatus can also in the scope of the appended'claims without departing from the spirit or sacrificing any of the advantages of the invention.

Having thus fully described the invention, what I claim as new and desire to protect by Letters Patent is 1. In an apparatus such as described, a battery box and a cover for the same, batteries disposed within the box and having contact posts extending therefrom, plungers movable. through the cover to and from the contact posts, contact members interposed between the contact posts and plungers and yieldingly held out of engagement with the contact posts, and conductors connected with the plungers.

2. In a device such as described, a battery box having a cover and batteries disposed within the battery box, said cover having openings therein, contactposts extending from the batteries in alinement with the in thebattery box, contact posts provided upon said batteries, saidcover having openings therein with Which'the contact posts aline, springs carried by the cover and surrounding the openings, plungers carried by the springs and adapted to pass through gsaid openings,'said springs normally yielding the plungers above the openings, contact members disposed within the cover between the contact posts and the plungers, and yieldingly forced away from the contact posts toward said cover, conductors leading from the battery box, eyes secured to the conductors and surrounding the plungers with said conductors passed through the upper convolutions of the springs which support the plungers and means for preventing engagement of the plungers with the contact members. f

' 4C. In a device such as described, a battery box including a cover, batteries within the box and having contact posts, plungers movable through openings formed in the cover to and from the contact posts, slides secured to the cover to close said openings and pre vent the plungers from entering the battery box, and conductors extending from the plungers.

In witness whereof I have hereunto set my hand.

Witnesses: v

JENNIE 'STRAOHAN, FRANCIS C. LOWE.

JOHN ANGUS MAGDONALD. 

